The current sense resistor is usually found in the switch mode power supply area. If you repair electronic equipment especially the switch mode power materials, the current noticing resistor is linked to the source pin of power FET (field effect transistor) and the other end to HOT GROUND. The worth of the current sense resistor is in the range of 0.1 ohms to about 1 ohm. In some cases where overload happen-the power area will blow and many of the time the elements altered are the fuse, power feed, PWM IC, Zenner diode and current sense resistor.

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